The present invention relates to an internal combustion engine which has at least one cylinder and a piston, and is provided with an external igniting means.
Internal combustion engines of the above mentioned general type are known in the art. One such internal combustion engine is disclosed, for example, in German Offenlegungsschrift No. 2,757,648. It has at least one cylinder, a piston movable in the cylinder, a combustion chamber between the piston and a cylinder head connected with the cylinder, and an additional internal combustion chamber connected with the first mentioned combustion chamber and arranged so that it has a round periphery and ends at an inlet valve, an injecting nozzle, igniting means formed as an ignition plug, and means for producing a twisted stream extending into the additional combustion chamber. The injecting nozzle opens into an aspirating conduit which guides the inlet valve and is formed as a multiple-hole nozzle. It injects several fuel jets, advantageously at the end of a respective aspiration step via the opened inlet valve into the additional combustion chamber. The ignition plug is arranged at the periphery of the additional combustion chamber. Because of the approximately uniform distribution of the fuel relative to the periphery of the additional combustion chamber, the fuel quantity in its greater part is entrained by air flowing into the cylinder to the same. For reliably igniting the fuel-air mixture, it is necessary to have a limited air surplus at least in the region of the igniting means. The known internal combustion engines can operate only with a low average air surplus or only with a low admixture of waste gas from the outlet. In these internal combustion engines the aspiration conduit is designed so that it serves as a means for generating a twisted stream during flowing in of air in the additional combustion chamber. Another means for generating a stream flowing into the additional combustion chamber and having a twist is known from German Offenlegungsschrift No. 3,008,124 and includes a gas guiding groove which is formed at a piston side directed to the cylinder head. At the end of a compression stroke it leads a stream from a cylinder formed by air or air-containing mixture with a tangential component into the additional combustion chamber and at its periphery. The twist in the additional combustion chamber acts so that the specifically heavier components of a mixture are displaced from fuel, air and in some cases waste gas toward the periphery of the combustion chamber, which leads to a fuel enrichment of the mixture along the periphery of this combustion chamber. In the known displacement piston combustion chamber machines, this enrichment of the fuel is limited to the region of the above mentioned periphery, inasmuch as, as described hereinabove, the great part of the injected fuel is entrained in the cylinder and during a subsequent compression stroke only a part is supplied back to the additional combustion chamber. The action of the centrifugal force is, however, too small to direct the supplied back fuel in the additional combustion chamber sufficiently to the periphery of the additional combustion chamber. The higher the temperature in the cylinder increases after the start of the internal combustion engine, the lower is the concentration of fuel at the periphery of the additional combustion chamber.
There is a possibility, described in U.S. Pat. No. 4,182,280, to arrange an injecting nozzle at the periphery of the additional combustion engine, and to inject fuel directly into this chamber during the compression stroke of the internal combustion engine. This results in an embossed layer of charge and has the disadvantage that the injecting nozzle is exposed to flames, whereby it is fast coked and changed, and is formed as an expensive high-pressure injecting nozzle and connected with a high-pressure injection pipe.